diff --git a/inventory-backend/app/api/v1/user.py b/inventory-backend/app/api/v1/user.py
index 1ca5e14..2327b02 100644
--- a/inventory-backend/app/api/v1/user.py
+++ b/inventory-backend/app/api/v1/user.py
@@ -35,7 +35,7 @@ def get_preferences():
 
 @user_bp.route('/preferences', methods=['PUT'])
 @jwt_required()
-@audit_log(module_name='系统', action_type='修改偏好配置')
+@audit_log(module='系统', action='修改偏好配置')
 def save_preferences():
     """
     保存/更新当前用户的 preferences 字段
diff --git a/inventory-backend/app/models/system.py b/inventory-backend/app/models/system.py
index 4246ba0..ce1ba80 100644
--- a/inventory-backend/app/models/system.py
+++ b/inventory-backend/app/models/system.py
@@ -22,7 +22,7 @@ class SysUser(db.Model):
     role = db.Column(db.String(50))
     status = db.Column(db.String(20), default='active')
     password_hash = db.Column(db.Text)
-    preferences = db.Column(db.JSON, default=dict)  # 用户偏好/个性化配置（如齐套监控列表）
+    preferences = db.Column(db.JSON, nullable=True)  # 用户偏好（如齐套监控列表）；Python层用 or {} 兜底
     created_at = db.Column(db.DateTime, default=beijing_time)
 
     def set_password(self, password):